Preoperative downregulation of long-noncoding RNA Meg3 in serum of patients with chronic postoperative pain after total knee replacement
AbstractAimsThe incidence of chronic pain after total knee replacement (TKR) is approx. 20%, why preoperative risk factors for the development of chronic postoperative pain are highly warranted. Studies have indicated that preoperative inflammatory markers hold prognostic information for the development of chronic postoperative pain. Long-non-coding-RNA (lncRNA) regulates the expression of genes related with e.g. inflammation. The current study aimed to investigate the preoperative influence of lncRNA on the development of chronic postoperative pain following TKR.Methods24 patients, who developed chronic postoperative pain and 12 patients with painfree recovery, were sampled from a larger clinical study. Preoperative serum samples were obtained from all patients and analyzed for potential lncRNA candidates. Briefly, total RNA was extracted from serum using miRNeasy Mini kit.cDNA samples were pre-amplified with RT2lncRNAPreAMP Primer Mix that contained specific set of primers to target genes of Human RT2lncRNA Inflammatory Response & Autoimmunity PCR Array. Further, the reaction (25μl) will be aliquoted into the wells of RT2lncRNA PCR Array Human Inflammatory Response & Autoimmunity. LncRNA-expressions were compared between the two groups using student’s t-test.Results19 patients were excluded due to the “cut-off” of the statistical analysis’s software that not included the samples because of genomic contamination, retro transcription and amplification’s low efficiency. A total of 13 patients were included (7 with pain, 6 without pain). The preliminary analysis found that the MEG3-lncRNA (implicated in tumor vascularization suppressing) were downregulated in patients who developed chronic postoperative pain compared to patients with a normal recovery (fold change: − 9.56, P < 0.05).ConclusionsPreoperative MEG-3 is downregulated in patients in risk of developing chronic postoperative pain following TKR. Future research, in larger cohorts should further investigate the role of MEG3 and hence the improvement of the cartilage vascularization and other lncRNAs as predictive indicators for the development of chronic postoperative pain.